U.S. Department of the Interior U.S. Geological Survey The Development of a National Hydrography Dataset for Semantic Geospatial Science Integration Dalia E. Varanka

National Hydrography Dataset (NHD)  Surface Water Drainage Network of the U.S.  Charts water data and models flow  One of four vector layers of The National Map  Esri ArcGIS file formats

Objectives  National Hydrography Dataset (NHD) Database ontology: develop for many purposes  Science data integration  Observations & Measurements ontology  Coastal and Marine Ecology Classification Standard  Basic Formal Ontology

Surface Water Ontology Module Upper Level Ontology All USGS Topographic Categories Specialist Domain NHD Esri Database Surface Water Coherent with

NHD Feature Semantics Converted triples are NHD segments with a URI using the unique id, and defined feature types, geometry, and other attributes.

NHD Semantics from Users Guide Object Space Event

NHD/Science Data Integration Upper Level Ontology All USGS Topographic Category Ontology Specialist Domain Data NHD Esri Data Surface Water Links inferred by

Fish Habitat Data Integration

Observation & Measurement (O&M) Ontology

Spatial Science Semantics Spatial Scale and other Relations Particular Variables Specific Populations

Coastal and Marine Ecology Classification Standard (CMECS)  FGDC standard; written to be spatially explicit for mapping and geospatial information application  Expressed in GIS (NOAA)

Categorical Spatial Relations  Subsystem: Lacustrine Littoral – The Littoral Subsystem includes shallow habitats in the Lacustrine System. The shoreward boundary of this subsystem extends to the landward limit of non-persistent emergents. The lakeward boundary includes all waters to a depth of 2 meters below Mean Lower Low Water (MLLW), or to the maximum extent of non-persistent emergents, whichever depth is greater.  Subsystem: Lacustrine Limnetic – The Limnetic Subsystem includes all deepwater habitats within the Lacustrine System. “Deepwater habitats” are those that occur at depths greater than 2 meters below MLLW—unless there are non-persistent emergents in those areas. In which case, “deepwater habits” are those beyond the limit of occurrence of non-persistent emergents.

Categorical Spatial Relations Spatial relation properties (verb/preposition pairs) extracted from topo feature definitions FLOW SubjectPredicateObject Water flowTHROUGHChannel (Linear deep part of a body of water) Underground waterflowTOThe surface of the Earth CAUSED Crater (Circular-shaped depression at the summit of a volcanic cone or one on the surface of the land) causedBYthe impact of a meteorite Crater (a manmade depression)an explosion (caldera, lua) FORM Crossing (A place where two or more routes of transportation) form a junction or intersection (overpass, underpass) REMOVED Mine (place where commercial minerals)removedFROMEarth Oilfield (area where petroleum is/was)Earth

Important because…  The spatial element of a class definition sets criteria for membership of individuals and for inferred semantics  Must be consistent through inference; these categories may possibly serve as superclasses for data integration

Asserted Spatial Properties

Graph Pattern as a Rule CONSTRUCT ?SB rdf:type :ShorewardBoundary Category Name WHERE ?SB :LandwardLimit geo:Contains :NonPersistentEmergents :LandwardLimit geo:Equals :ShorewardBoundary Category Criteria Construct triples to comply with a graph pattern using:  Category names as subject or object,  GeoSPARQL properties  Variables

Surface Water / Upper Level Semantic Integration Upper Level Ontology All USGS Topographic Category Ontology Science Domain Ontology NHD Esri Database Ontology Surface Water Links inferred by

Our Interest in Basic Formal Ontology (BFO)  Ontology modeling best practices  Strong general environment/science specification approach  Recognition of the role of geographic features and space  Approaches to processes and change

Entity ContinuantOccurant Independent Continuant Dependent Continuant Material Entity Immaterial Entity Site Boundary Spatial Region ObjectFiat Object Part Object Aggregate Hill Mountain Range Mount Footprint Area Footprint Perimeter Footprint Area

Entity ContinuantOccurant Independent Continuant Dependent Continuant QualityRealizable Entity ReserveNational Park

Entity ContinuantOccurant Process Process BoundaryTemporal Region Spatiotemporal Region Disturbance Disturbance Extent Period of Disturbance Disturbed

U.S. Department of the Interior U.S. Geological Survey Thank you Northern Flicker